Ecology of Fall Migrating Sora in MissouriAuriel M.V. Fournier1, David G. Krementz2, Doreen C. Mengel3, Andy H. Raedeke3 1Arkansas Cooperative Fish and Wildlife Research Unit, Department of Biological Sciences, University of Arkansas (amvander@uark.edu)2U.S. Geological Survey, Arkansas Cooperative Fish and Wildlife Research Unit, Department of Biological Sciences, University of Arkansas 3Missouri Department of Conservation, Resource Science Division, Columbia, Missouri

• Little is known about the timing or habitat use of Sora during their fall migration.

• Within the Mississippi Flyway a portion of remaining wetlands are located on intensively managed public areas. Wetland management techniques include soil disturbance and water level manipulation to promote desired plant communities and structures.

Location of study areas across the state of Missouri, USA in four regions: NW, NC, NE & SE.

NWR = National Wildlife RefugeCA = Conservation Area

Introduction

AR Coop Unit/Justin Lehman

• We conducted nocturnal spotlight surveys from ATVs on 12 publically-managed wetland complexes across the state of Missouri.

• A series of wetland impoundments at each complex were surveyed for two hours each night.

• Our season was divided into three survey rounds. Each series of impoundments was visited twice per round.

Methods

Round 1: Aug 15-30, Round 2 : Sept 2-19, Round 3: Sept 21-Oct 7PE: Perennial Emergent, UP: Upland, MS: Moist Soil

Discussion• Due to the drought conditions in 2012

water was limited on the landscape and almost exclusively restricted to moist soil units. This drought may have driven the selections of these Sora more than the habitat or disturbance. The water in 2012 was limited to moist soil units by managers to prepare those units for waterfowl migration.

• We anticipate that in a more normal precipitation year there may be different patterns of habitat use.

Future Work• We are currently in our 2nd field season

and will have a 3rd in 2014.

• This fall we are capturing rails to collect feathers for stable isotope analysis to determine the origin of rails using these sites.

• We are also deploying VHF radios this fall to determine detection probability.

Acknowledgements• We would like to thank the U.S. Fish and Wildlife

Service, the Missouri Department of Conservation and the U.S. Geological Survey Arkansas Cooperative Fish and Wildlife Research Unit for funding and assisting with this study.

• We would like to thank C. Crisler, D. Welchert, R. Bell, C. Freeman, S. Whitson, M. Flaspohler, R. Kelly, M. Hanan, J. Wilson, G. Calvert, B. Pendley, K. Brunke, M. Bowyer and K. Cordell for their help in planning this project.

• Special thanks to M. Boone, L. Brinkman, D. Datlof, J. Lehman, and N. Seeger for their diligent and enthusiastic work in the field.

• All of our study sites experienced exceptional or extreme drought conditions in the summer/fall 2012.

Phenology• We detected over 1,800

Sora in the fall of 2012.

• The number of Sora increased throughout the season.

Habitat• In 2012, we observed a

strong region and round effect across all surveys and were not able to create any state wide models.

• Because of this effect we produced a set of individual region models using R package ‘unmarked’ for both habitat type and disturbance regime.

• Moist soil units had the highest densities of Soras when compared to other habitat types.

• Impoundments with disturbance through discing had the highest densities of Sora.

Round 1: Aug 15-30, Round 2 : Sept 2-19, Round 3: Sept 21-Oct 7

Moist Soil Habitats Have Higher Sora Density than Perennial Emergent or Upland

Disced Habitats Have Higher Sora Density than Mowed or Undisturbed Habitats

Number of Sora Observed Increased Throughout the Season

Results